Just a quick question: When a UMTS network is deployed, do voice calls go out over the UMTS network as well, or is UMTS just active for data while GSM is retained for voice? The vast majority of people only use their cell phones for voice communication, and I was wondering if UMTS improves voice call quality or if it is even used for voice to begin with. Thanks!
You can do voice over UTMS and it will fall back to GSM if no UTMS is available. I'm not sure of the quality but I've read that is some better than GSM. UTMS can do vocie and data at the same time.
Is that right? Why would you need two radios to do voice and data at the same time? I thought the voice/data split was done at the mobile at decoding time similar to the way you can carry a VoIP call and use the Internet at the same time using a single carrier line such as a WiFi router, a cable modem or DSL. I can understand, however, you would need two radios for both networks, one for GSM and another one for UMTS, but why when using UMTS only?
